Data and Methodology Core: Primary responsibility for biostatistical and methodological consultation and basic data management and data analysis support for the Center projects will be provided by the NPI Biostatistics Core (NPIStat, Jim Mintz, Ph.D., Director) of the UCLA Neuropsychiatric Institute. NPIStat has six part-time faculty, four at the Professor level, biostatisticians and other support personnel such as statistical programmers. Two additional senior faculty members (one from Biostatistics and the other from Education) who are not affiliated with the NPIStat Core have been recruited to provide highly specialized statistical consulting in their areas of expertise as part of the Data and Methodology Core of this Center. Dr. Mintz will be the primary NPIStat faculty member who is responsible for this Center Core. He will provide the direct consulting services, supervise other personnel, and be a liaison to other consulting faculty as required. The Core will provide ongoing consultation to Center researchers on data analysis, design of new projects, and conduct of ongoing experiments. The Core will responsible for creating and maintaining the Center's centralized database as a repository of Center data, and will provide requisite software interfaces to enable Center researchers to enter data reliably, access it readily, and analyze it properly. The Core maintains a local area network of powerful IBM-compatible microcomputers in the NPIStat offices and desktop computers in the project offices. The Center's data management system will enable the rapid and accurate entry of data from all relevant evaluations and assessments. This will provide a central repository for all Center data, which includes the research data from the Clinical Cores and summary variables from the projects. The centralized files will be ready for periodic report generation for administrative purposes and ongoing statistical analysis. In general, data management and analysis will be performed using the SAS library. SAS is a comprehensive database and statistical software library in wide use in biomedical research. System and data integrity and system security and patient confidentiality will be given priority and maintained throughout the Center research.